In product discovery, our goal is to test many ideas with real users. The faster we test each idea, the more ideas we test. And the more ideas we test, the better our chances of discovering a great product opportunity.

What is prototyping?

A prototype is a rough approximation of what a finished product could be. Prototyping is the process of creating that approximation.

If you’ve ever hung a picture on your wall, you’ve made a prototype. “How does this look?” you asked, holding up the picture. “A little to the left,” your spouse or roommate says. This is a prototype: it looks very similar to the end product, but you try out variations quickly and easily — without hammering a bunch of nails into your wall. But the prototype is not the end goal, since you cannot stand there forever holding the picture. So once you find the right spot, you drive in a nail and hang the picture on it: and that’s your finished product.

Prototyping is an immensely powerful technique. It helps us gather our thoughts. It helps us compare options. It helps us have a healthy debate on our product development team. It helps us get buy-in from stakeholders. And it’s how we test and thus validate or falsify our product hypotheses with users, without needing to invest in the cost of building a finished product.

While creating potential product designs, we often use wireframes. Wireframes are a sketch of how the product might look, and a central technique in the brainstorming and design process. Prototypes differ from wireframes in that they are interactive. A prototype is something that we, and our users, can try out.

There are many approaches and tools for creating prototypes, including clickable wireframes (software), 3D printing (physical products), and breadboards (electronics). I’ll go into more detail on those another time. But first, a story about prototyping from a successful product company.

Real-world example: DODOCase

DODOCase makes iPad cases that have the look and feel of a hardcover book.

Founder Patrick Buckley, working on the first version of the product, needed to find a way to hold an iPad inside the hardcover book binding. His idea: hold the tablet in place with a wooden tray.

Pat created his physical prototypes using a device called a CNC router which can carve a design created on a computer out of a block of material. Rather than buying one of these machines, he purchased a low-cost membership at his local TechShop where he could access a CNC device.

(right) One of the first DODOCase tray prototypes, a very simple side rail with no space for cords. (left) The finished product, with a multi-part tray including cord cutouts.

One question he sought to answer with his prototype was: can a tray effectively hold the iPad in the book binding? Early versions of the tray failed at this, but he iterated on the design until he found one that held the tablet in place.

Another question he had was: how can the user access the power plug, audio plug, and volume buttons without the tray blocking access? He tried cutting gaps, but discovered that this weakened the tray and caused it to break too easily. He iterated on different thicknesses of the tray and size and shape of the cut gaps. He was thus able to explore the physical capabilities of his material and his design.

The DODOCase example demonstrates even physical products can do fast, cheap prototyping. Pat created dozens of prototypes over the span of several weeks, at a cost of about $500 (materials and a TechShop membership).

Pat’s story also helps us understand the true purpose of a prototype. In creating the prototypes he sought to discover the answers to questions about what was possible with the tools, with the materials, and in the design.

Prototypes answer questions

It’s important we understand that a prototype is not a finished product. The purpose of a prototype is to answer a question or to test a hypothesis.

A question for a software product could be: can we accommodate several different modes of operation on a single screen, or will the resulting design be too cluttered? Sketching out some designs as clickable wireframes may answer this question without even needing to user test.

A question for a physical product could be: what’s the maximum size we can make our product and still have it be comfortable to grip one-handedly? Creating a clay or 3D-printed prototype gives us an object we can hand to our test users and see how they hold it.

Benefits of prototyping

The number one reason to prototype is to test your idea with users, which I’ll discuss in a future post. But even before prototypes make it in front of users, there are many benefits for your team and your company.

Prototyping helps us gather our thoughts. Even if you’re working on a small project just for yourself, the process of making something tangible that shows rather than tells what the product will do is extremely focusing.

Prototyping helps us compare options. Sometimes it makes sense to create multiple, competing prototypes for comparison. It’s often the case that when we see several options side-by-side, it makes the best option dramatically apparent.

Prototyping keeps team debates healthy and grounded. Meetings can go around in unproductive circles as the team debates abstract possibilities about what to build. Prototypes can help change this endless speculation (what Tom Chi calls “guess-a-thons”) into a discussion about tangible details. Faced with a concrete example of how it will look and work, everyone on the team may instinctively agree to which option to pursue — and if not, it provides a basis for discussion about specifics rather than vague and abstract possibilities.

Prototyping helps us get buy-in from stakeholders. If you’ve ever done contract work — that is, building something to your client’s specification in exchange for an hourly rate — you know how common it is that the client sees the finished product and says, “Yeah, I was picturing something a little different…” Prototyping gives us something that looks and feels something like the real thing, and lets us put it in front of stakeholders like clients, senior management, or people in our company who aren’t working directly on the development of this particular feature.

Conclusion

Prototyping helps us answer questions, test hypotheses, and get everyone in our company on the same page about what we’re doing. Prototypes are not products and we shouldn’t mistake them for such. In the next post, I’ll talk about the disposable nature of prototypes and how to select an appropriate level of fidelity.